Fluoroelastomers are known to have excellent mechanical properties, heat resistance, weather resistance, and chemical resistance, for example. Such beneficial properties render fluoroelastomers useful, for example, as O-rings, seals, hoses, skid materials, and coatings (e.g., metal gasket coating for automobiles) that may be exposed to elevated temperatures or corrosive environments. Fluoroelastomers have been found useful in the automotive, chemical processing, semiconductor, aerospace, and petroleum industries, among others.
Fluoroelastomers are typically prepared by combining an amorphous fluoropolymer, sometimes referred to as a fluoroelastomer gum, with one or more curatives, shaping the resulting curable composition into a desired shape, and curing the curable composition. The amorphous fluoropolymer often includes a cure site, which is a functional group incorporated into the amorphous fluoropolymer backbone capable of reacting with a certain curative.
Fluoroplastic particles of various sizes and either having a cure site or not having a cure site have been incorporated into fluoroelastomer matrices to improve one or more properties. See, for example, U.S. Pat. No. 7,476,711 (Takahashi et al.); U.S. Pat. No. 7,022,773 (Albano et al.); U.S. Pat. No. 7,019,083 (Grootaert et al.); U.S. Pat. No. 6,756,445 (Irie et al.); U.S. Pat. No. 6,734,254 (Worm et al.); U.S. Pat. No. 6,395,834 (Albano et al.); and U.S. Pat. Appl. Pub. No. 2011/0245402 (Stanga et al.).